Qualitative and quantitative analysis of phytoplankton in Ramala Lake

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1 19 (1&2) 79-84, 2018 ISSN (Print) (Online) Abstracted and Indexed Qualitative and quantitative analysis of phytoplankton in Ramala Lake Kulkarni Rajlaxmi R. 1, Zade S.B. 2 Received: Revised: Accepted: Abstract Plankton are important biotic component of aquatic habitat. They do determine the trophic status and quality of water. The phytoplankton is the base of most of the lake food web. It forms a bulk of food for zooplankton, fishes and other aquatic organisms. The biodiversity of phytoplankton and zooplankton in any water body shows a correlation with reference to their occurrences and physic-chemical factors. The present paper is an attempt to enumerate the phytoplanktonic diversity of the Ramala Lake, Chandrapur, and Maharashtra. Data is collected during the different seasons from November 2006 to October The plankton community showed the seasonal fluctuations. The phytoplankton population of Ramala Lake was found to be composed of four major groups namely Chlorophyceae (48.40%), Bacillariophyceae (24.81%), Myxophyceae (22.44%) and Euglenophyceae (4.32%). The class Chlorophyceae represented by 11 species stood first quantitatively and qualitatively, Bailloriophyceae by 7 species, Myxophyceae by 5 and Euglenophyceae by only 2 species. Key words: Phytoplankton, Zooplankton, diversity, productivity, biological indicator. Introduction Phytoplankton is a base of most of freshwater and (marine) food web. Phytoplankton, which includes blue-green algae, green algae, diatoms, desmids, euglenoid etc. are very important among aquatic flora. They are ecologically important as they form the basic link in the food chain of aquatic ecosystem. Phytoplankton is the pioneer of an aquatic environment food chain. The productivity of an aquatic environment is directly correlated with the density of phytoplankton. Number and species of phytoplankton serves to determine the quality of water body. The maintenance of healthy aquatic ecosystem depends on abiotic properties of water and biological diversity of ecosystem (Krishnan et al., 1999). The planktonic study is very useful tool for assessment of water quality. Among the biotic communities phytoplankton constitute the first stage in tropic level by virtue of their transduction capacity of environmental radiant energy into the biological energy through photosynthesis. Also referred to as primary productivity, the magnitude of photosynthesis Author s Address 1 Sardar Patel College, Chandrapur 2 PGTD Zoology, RTM university, Nagpur. .: kulkarnirajlaxmi@gmail.com Copyright by ASEA All rights of reproduction in any form reserved 79 energy fixation depends upon diversity and biomass of phytoplankton. Phytoplankton also plays important role as food for herbivorous animals. They also are the biological indicators of water quality. The present phytoplankton study was undertaken in local fresh water body of Chandrapur city which is influenced by several anthropogenic activities like discharge of effluents, domestic washing, sewage, idol immersion and commercial fishery. Ramala Lake is a historical impoundment and main embankment of lake is a part of fort wall built up around Chandrapur city by Gond king (Raja). Lake harbors a wide variety of plant and animal species and plays an important role in conservation of nature. It is sole recreational water body situated in the heart of city. It is the only reminisce of greenery in the most polluted and populated city. Material and Methods Samples for phytoplankton studies were, collected from three sampling stations monthly at regular interval between the study periods November 2005 to October The samples were collected between 7.00 a.m. to 9.00 a.m. 50 liters of water sample was filtered through plankton net made of

2 Kulkarni and Zade bolting silk (number 25) with mesh size 64µm. The collected samples were allowed to settle by adding Lugol s iodine. Normally sedimentation requires 24 hrs. After which supernatant was removed and concentrate was made up to 20ml with 4% formalin. The identification of phytoplankton was done with the keys Sehgal (1983), Adoni (1985), Presscot (1954) and APHA (1985). Result and discussion Phytoplankton, being the basic producer of food chain, is governed by the interrelation of a number of physico-chemical and biological conditions of water body. They are basically chlorophyll bearing suspended particles represented by four main groups like Chlorophyceae, Bacillariophyceae, Myxophyceae and Euglenophyceae.The water from three different sites of Ramala Lake was analyzed for quantitative and qualitative study of plankton in each month for the period of one year. Qualitative analysis of phytoplankton Water samples collected from three different sites were observed microscopically to analyze the plankton. Observation revealed the phytoplankton belonging to four major groups viz Chlorophyceae. Total 25 species of phytoplankton were found and identified during study period. The group Chlorophyceae was dominating group represented by II species belonging to five orders. The members included, Chlamydomonas, Volvox, Chlorella, Pediastrum, Hydrodyctyon, Scenedesmus, Tetradon, Spirogyra, Zygnema, Closterium and Cosmarium sp.at all the three stations Chlorophyceae were maximum in number in winter months followed by summer.some of the members from this group viz. Volvox and Chlorella found throughout the year during study period at all the three sampling stations. Spirogyra and Pediastrum were dominant among these members.the group Bacillariophyceae forms observed were 7 species viz. Cymbella, Navicula, Nitzchia, Fragilaria, Pinnularia. Gomphonema and Synendra. The members of this group were almost found distributed throughout the lake. The pollution indicator species like Cymbella, Navicula and Nitzchia found at station II. The group Myxophyceae was represented by 5 species. The group was found in second dominant position at station II regarding numerical abundance. The species identified from this group were Microcystis, Spirulina, Nostoc, Anabena, Oscillatoria; Spirulina was the dominant member present almost throughout the study period. Microcystis and Nostoc were also found in major proportion. Only two species were recorded from the group Euglenophyceae viz. Euglena and Phacus. Regarding numerical density, group Chlorophyceae emerged as a dominant group (48.40%). Group Bacillariophyceae (24.81%) as second dominant, followed by Myxophyceae (22.4%) and Euglenophyceae (4.32%). Number and species of phytoplankton serves to determine the quality of water body. Phytoplankton forms a bulk of food for zooplankton, fishes and other aquatic organisms. The planktonic study is very useful tool for assessment of water quality. The phytoplankton composition of Ramala Lake was recorded in the range from 467 units/l to 1385 units/l. The highest numerical density of phytoplankton was recorded in the month of May, June, December and January. Minimum density was found in August and September. Kalyani et al., (1999) have recorded bimodal peak of phytoplankton population i.e. summer peak in April and winter peak in December. Similar peak in phytoplankton population were observed by Das and Shrivastava (1959). The effect of temperature on phytoplankton cannot be separated from the effect of light since both the factors are interrelated in photosynthesis. The enhanced growth of phytoplankton in summer could be attributed to increased temperature and light during summer.enormous anthropogenic activities and heavy discharge of sewage, resulted in enrichment of nutrients, proliferation of algal species takes place which in turn enhances trophic status of Lake. Phytoplankton population of Ramala lake was composed of four major groups namely Chlorophyceae (48.40%), Bacillariophyceae (24.81%), Myxophyceae (22.44%) and Euglenophyceae (4.32%). Meshram and Dhande (2000) and Pailwan (2005) have recorded almost similar species composition of phytoplankton in Wadali Lake, Amaravati. Maximum density of Chlorophyceae was recorded in winter followed by summer. Monsoon months showed minimum density of Chlorophyceae. Chlorophyceae was represented by 11 different species. 80

3 Qualitative and quantitative analysis of phytoplankton in Ramala Lake Table 1. Phytoplankton species recorded from Ramala Lake during study period November 2005 October 2007 Sr. Species Station I Station II Station III No. Chlorphyceae 1 Spirogyra sp Costerium sp Cosmarium sp Pediastrum sp Chlorella sp Hydrodictyon sp Dedogonium sp Scenedesmus sp Zygnema sp Volvox Chlamydomonas Bacillariophyceae 1 Navicula sp Nitzchia sp.* Cymbella sp.* Fragillaria sp* Gomphonema sp Pinhullaria sp Synedra sp Myxophyceae 1 Microcystis sp.* Anabena sp Nostoc sp Oscillatoria sp.* Spirulina sp Euglenophyceae 1 Euglena sp Phacus sp

4 Kulkarni and Zade Table 2. Quantitative analysis of total Phytoplankton from November 2005 to October 2006 MONTH Station I Station II Station III Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sept Oct Table 3. Quantitative analysis of total Phytoplankton from November 2005 to October 2006 MONTH Station I Station II Station III Nov Dec Jan Feb Mar Apr May Jun Jul Aug Sept Oct Fig 1.Percentage composition of Phytoplankton in Ramala Lake 82

5 Qualitative and quantitative analysis of phytoplankton in Ramala Lake Seasonal data revealed that maximum Chlorophyceae members were present in winter. The members from this group which dominated throughout the study period were Hydrodictyon, Pediastrum, Dedogonium and Chlorella. Spirogyra, Closterium and Scenedesmus were found predominantly at station II and in some months within study period indicating pollution (Meshram and Dhande, 2000). The dominance of this group during winter (November-December) coinciding with low temperature and high dissolved oxygen content has been reported by Venkateshwarlu (1969). Green algae prefer water with comparatively higher concentration of dissolved oxygen. The temperature is considered to be an important factor in the periodicity of the Chlorococcales population. The enhanced growth of green algae in winter, followed by summer may be due to high dissolved oxygen content in winter, maximum transparency and optimum ph. The members of Bacillariophyceae dominated the lake and were found distributed throughout the lake. The group was represented by 7 species. Although few species of diatoms in the present investigation have been recorded, they differ both in quality and quantity in the study lake. Seasonal abundance of this group occurred in summer. Pinnularia, Fragillaria and Navicula were constantly encountered from this group. Nitzehia, Navicula and Cymbella which are known as pollution indicator species were observed predominantly in summer along with other phytoplankton species. Navicula and Nitzchia are commonly found in moderately polluted water. These were observed throughout the study period, but higher number was observed in summer (February - May). Dominance of this group indicates moderate pollution status of these tanks. Similar results have been reported by Shashikant (1979). Members of Myxophyceae are ubiquitous in natural water and many times forms temporary or permanent blooms in the polluted water body. The Myxophyceae was represented by five species, Microcystis, Anabena, Nostoc, Oscillatoria and Spirulina. Microcystis species were present throughout the monsoon. The occurrence of Microcystis, the toxin producing blue green in blooms is a significant feature of tropical water (Wetzel, 1975). The blue green algae are frequently involved in 83 contamination of water body. Various physical, chemical and biological circumstances must be taken into consideration for understanding plankton population. Parmasivan and Sreenivasan (1981) have reported that the polluted water bodies exhibit heavy growth of blue green algae which also dominate over Chlorophyceae and Bacillariophyceae. Myxophyceae found as a second dominant group only at station II might be due to pollution because of several anthropogenic activities. Euglenophyceae were represented by only two members, Euglena and Phacus. Seasonal data revealed maximum density of Euglenophyceae in winter followed by summer. Minimum density was found during monsoon months at all the three stations. The Euglenophyceae are in greater number at organically polluted water bodies. Palmer (1969) showed that the Euglenophyceae are the biological indicators of organic pollution. In the present study, Euglena and Phacus were found occasionally in winter and summer months and that too in very less quantity. The group as a whole is facultatively heterotrophic and generally abundant in water rich in organic matter (Hutchinson, 1957). Conclusion The studies of Biological Characteristics include the study of phytoplankton, zooplankton and primary productivity. Plankton due to its key role in ecosystem is directly related to fish potential. Any change in the physio-chemical environment has got its effect on biotic communities due to the fact that different species of flora and fauna exhibit variation in their responses to the altered water quality. Phytoplankton were represented by four groups, Bailloriophyceae (24.81%),Chlorophyceae (48.40%), Myxophyceae (22.4%) and Euglenophyceae (4.32%), phytoplankton exhibited a bimodal pattern of seasonal fluctuations, as such two peaks were recorded, one in May, June and other in winter. Total phytoplankton showed a positive correlation with temperature, ph, alkalinity, nutrient groups, phosphates, nitrates and chloride. Phosphate and nitrate play a vital role in governing the presence of aquatic system. Phosphate is an important nutrient required for the growth of phytoplankton in fresh water body. Phosphate is the major nutrient that triggers eutrophication. In natural water, phosphates are

6 Kulkarni and Zade present in small amount. The water receiving untreated domestic sewage can indicate presence of phosphate. The range of phosphates in the present investigation was found to be 0.5 mg/l to 2.1 mg/l, showing maximum concentration in summer. It can be attributed to the addition of detergents and also due to release of phosphates from dead and decayed plankton and macroinvertebrates. Thus positive correlation was seen in phosphate content and number of phytoplankton. The winter months showed higher phytoplankton density followed by summer and rainy months. The lower densities during rainy months may be due to high turbidity, low light intensity, cloudy weather and more water coverage with rains. Various physical, chemical and biological circumstances must be taken into consideration for understanding plankton population. Temperature and light are most important factors affecting growth of phytoplankton and both factors are interrelated in photosynthesis. Enhanced growth of phytoplankton in summer could be attributed to increased temperature and light. Some pollution indicator species such as Nitzchia, Navicula and Cymbella are observed predominantly in summer. Navicula and Nitzchia are commonly found in moderately polluted water. Therefore it can be concluded that the lake under study is moderately polluted and in future care should be taken for conservation of water body. References APHA, American Public Health Association Standard method for the examination of water and waste water. 14 th Ed. APHA-AWWA-WPCF. Washington, D.C. : Adoni, A.D Workbook on Limnology; Indian MAB Committee, Depts. of Environment, Govt. of India. Krishnan Hari, Thomas K. Sabu, Sunil George, Paul Murugan, R. Sathish mundayoor and Das, M.r A study on the distribution and ecology of phytoplankton in the Kuttanad wetland ecosystem, Kerala. Poll Res. 18(3): Hutchinson, G.B A treatise on limnology vol. II John Wiley and Sons, New York, Kalyani, Y. and M.A. Singara Charya Phytoplankton dynamics in Bhadrakali lake,warangal,(a.p.) In : Fresh water ecosystem of India. (Ed. K. Vijaykumar) Daya publishing house Delhi.: Meshram, C.B. and R.R. Dhande Algal diversity with respect to pollution status of Wadali Lake, Amravati, (M.S.) India. J. Aqua. Biol. 15 (1&2): 1-5. Pailwan, I.F Limnology and fisheries potential of perennial tanks of Kolhapur district, Kolhapur. Ph.D. Thesis, Shivaji University, Kolhapur. Palmer, C.M A composite rating of algae tolerating organic pollution. J. Phycol., 5: Paramasivam, M. and Sreenivasan, A Changes in algal flora due to pollution in Cauvery river. Ind. J. Environ. Hlth, 23: Prescott, G.W The algae A : Review. Thomas Nelson and sons. Ltd. London: Sehgal, K.L Planktonic copepods of fresh water, ecosystems INTERPRINT, New Delhi. Shashikant Diatoms as indicators of water quality.proc. Sym.Biol: Venkateswarlu, V Ecology of Algae in the River Moosi, Hyderabad with special reference to water pollution I. Physico-chemical complexes. Hydrobiologia 33: Wetzel, R.G Philadelphia L:743. Limnology. B.Saunders Company, Das, S.M. and V.K. Shrivastava Studies on freshwater plankton III. Qualitative. Composition and Seasonal fluctuation in plankton components, Proc. Nat. Acad. Sci. India, 29: